I think John is right, the first is the number of seconds in the timespan listed. And the second certainly looks like a unix timestamp to me. So here's how you can get what you want from these sets of numbers:
1) For the first number, simply divide the number by the seconds in a given time span and use floor():
$timeElapsed = 154496; // in this case
$weeksElapsed = floor($timeElapsed / 604800);
$remainder = $timeElapsed % 604800;
$daysElapsed = floor($remainder / 86400);
etc...
2) For the second number, you can do the same thing by first getting the current timestamp and then subtracting the given timestamp from it:
$lastOnline = 1397087222; // again, in this case
$currentTimestamp = time();
$elapsedSinceLastLogin = $currentTimestamp - $lastonline;
$weeksSinceLastLogin = floor($elapsedSinceLastLogin / 604800);
etc...